An X-ray imaging apparatus is equipment for irradiating X-rays on an object and analyzing the X-rays transmitted through the object to thereby show the internal structure of the object. The X-ray imaging apparatus can image the internal structure of an object using a fact that different tissues in the object have different attenuation coefficients obtained by digitizing degrees to which the respective tissues transmit X-rays.
Meanwhile, in order to set X-ray irradiation conditions, information about Source to Object Distance (SOD) representing the distance between an X-ray source and an object or Source to Image receptor Distance (SID) representing the distance between the X-ray source and an X-ray detector is needed.
Also, in order to automatically align the poses and locations of the X-ray source and the X-ray detector, information about the pose and location of the X-ray detector is needed in addition to information about the distance between the X-ray source and the X-ray detector.